ELFT HÍRADÓ

[Edina Szirmai <eszirmai AT phy.bme.hu>]

                   MEGHÍVÓ

az BME-MTA "Egzotikus Kvantum Fázisok"
 kutatócsoport következő szemináriumára:



                Yoshio Kuramoto
 (Institute of Materials Structure Science,
           KEK, Tsukuba, Japán)

 Orthogonality and exciton correlations
          leading to Kondo-like effect


In certain Sm systems with mixed valence such as SmOs4Sb12 and SmT2Al20
with T=Ti, V, Cr, Ta, etc, the resistivity and specific heat show behaviors
reminiscent of the Kondo effect.  However, the behaviors are almost
independent of applied magnetic field.  We ascribe the Kondo-like behavior
to charge correlations.  Acccoding to our model, the effective
hybridization of Sm 4f-electrons is reduced by the orthogonality effect
with the Coulomb interaction U between 4f and conduction electrons. The
Coulomb interaction also acts to enhance the hybridization via the
exciton-like correlation.  The orthogonality effect becomes dominant as U
and/or the number of conduction channels increases, and eventually makes
the effective hybridization vanish.  We combine the continuous-time quantum
Monte Carlo calculation and the analytic theory to derive the dynamics in
the wide frequency range.


Az előadás helye:  BME F III. épület, mfsz, szemináriumi szoba.
Ideje: 2015. november 2. hétfő, 14:15.



Minden érdeklődőt szeretettel várunk!

                            Szirmai Edina





-- 
Edina Szirmai
Department of Theoretical Physics,
Budapest University of Technology and Economics
Budafoki ut 8.
Budapest, Hungary
Tel:(+36-1) 463-4107
Fax:(+36-1) 463-3567
www.phy.bme.hu/~eszirmai